title: Inhibitory effect of mesenchymal stem cells on lymphocyte proliferation.
abstract: We investigated the mechanism underlying the inhibitory effect of rat mesenchymal stem cells (MSCs) on non-specific mitogen-stimulated lymphocytes (LCs) and lymphoblasts (LBs). We used MSCs of passages 2-8 prepared from Sprague-Dawley (SD) rats. LCs were isolated from the spleens of SD rats. Mixed LCs reactions of mitomycin C-treated MSCs with concanavalin A (ConA)-stimulated LCs or LBs were performed, and the proliferation inhibition effect was tested by MTS assay. The cytotoxicity of MSCs against naïve and ConA-stimulated LBs was detected, after co-culturing for 24 h, by lactate dehydrogenase release assay. The rate of apoptosis of ConA-stimulated LBs was measured by flow cytometry after incubation with MSCs for 9 h in the ratio 10:1. The MSCs were treated with Fas ligand (FasL), transforming growth factor (TGF)-beta, and interleukin (IL)-10 blocking antibodies and co-cultured with ConA-stimulated LBs to observe the apoptosis and growth inhibitory effect. The main outcomes were bone marrow-derived adherent CD29+, CD44+, CD45-, CD54+, CD95+, and SH-2+ MSCs. FasL, TGF-beta, and IL-10 production by MSCs were visualized by immunocytochemical analysis. MSCs exhibited a dose-dependent growth inhibitory effect on ConA-stimulated LCs and LBs. When treated with anti-FasL and anti-IL-10 blocking antibodies, the inhibitory effect of MSCs on LBs proliferation, and the effect of apoptosis induction on LBs decreased. Anti-TGF-beta blocking antibody treatment did not significantly influence MSCs. Therefore, the inhibitory effects of MSCs against activated LBs were significantly stronger than that against naïve LCs. FasL and IL-10, rather than TGF-beta, play important roles in the immunosuppressive effects of MSCs.
authors.affiliation: Key Laboratory of Transplant Engineering and Immunology, Ministry of Health, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Gao
authors.forename: Younan
authors.initials: Y
authors.lastname: Chen
authors.forename: Lingling
authors.initials: L
authors.lastname: Wei
authors.forename: Shengfu
authors.initials: S
authors.lastname: Li
authors.forename: Xi
authors.initials: X
authors.lastname: Jin
authors.forename: Cong
authors.initials: C
authors.lastname: Cong
authors.forename: Yu
authors.initials: Y
authors.lastname: Yuan
authors.forename: Dan
authors.initials: D
authors.lastname: Long
authors.forename: Youping
authors.initials: Y
authors.lastname: Li
authors.forename: Jingqiu
authors.initials: J
authors.lastname: Cheng
authors.forename: Yanrong
authors.initials: Y
authors.lastname: Lu
mesh_terms: D000818:Animals; D017209:Apoptosis; D049109:Cell Proliferation; D018920:Coculture Techniques; D003208:Concanavalin A / Q000378:metabolism; D053222:Fas Ligand Protein / Q000378:metabolism; D016753:Interleukin-10 / Q000378:metabolism; D045022:Lactate Dehydrogenases / Q000378:metabolism; D008213:Lymphocyte Activation; D007959:Lymphocyte Culture Test, Mixed; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D008297:Male; D059630:Mesenchymal Stem Cells / Q000276:immunology / Q000378:metabolism / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D016212:Transforming Growth Factor beta / Q000378:metabolism
chemical_list: D053222:Fas Ligand Protein; D016212:Transforming Growth Factor beta; D003208:Concanavalin A; D016753:Interleukin-10; D045022:Lactate Dehydrogenases